The American Society for Rickettsiology (ASR) has a long history of promoting scientific interactions among world-renowned experts and junior investigators to enhance understanding of obligately intracellular bacteria and arthropod-borne rickettsial diseases, which include emerging zoonoses, have important biothreat implications, and are considered neglected. The 27th Meeting of the ASR will be held on June 20-23, 2015 in Olympic Valley, California. This thought-provoking meeting will include a five-session focused workshop titled Rickettsiales: Disease Models, Immunity and Vaccine Development to be held in conjunction with the ASR meeting, that will address critical gaps and emphasize the latest advances in models of disease, host responses and immunity, and vaccine development. There is no vaccine for any rickettsial disease, and understanding of protective immunity and immunopathologic immune mechanisms is limited. These gaps in our understanding were recently identified in the 2011 Institute of Medicine (IOM)-sponsored workshop on tick- borne diseases. Keystone conferences are scheduled in 2015 that will address veterinary pathogens and vector transmission, but this proposed workshop is unique in that it is the only one to comprehensively address established and emerging human rickettsial diseases. Topics will include advances in disease models, immunity, and vaccine development, and will thereby address the prevention gap identified in the IOM report. Ten scientists that presented or contributed to the IOM report have agreed to serve on the workshop or scientific committees to ensure that this workshop addresses the gaps identified in the report. The goal of this conference and integrated workshop is to stimulate and facilitate interdisciplinary interactions among junior and established researchers with mutual interests and varied expertise in obligately intracellular pathogen. The expertise of these investigators encompasses the fields of epidemiology, genomics, molecular biology, vector biology, cellular biology, immunology, diagnostics and vaccinology. The conference will provide updates on the state-of-the science, catalyze collaborations, and to identify and develop new strategies to address gaps in disease prevention. Specific objectives of this conference are to provide a forum to encourage scientific exchange among the estimated 200 participants that represent experts from academia, government and industry, through talks by keynote/plenary speakers and by national and international leaders in the field as well as junior scientists and trainees. The conference will also provide a program that will convey cutting-edge scientific advances in rickettsiology and highlights the latest developments in the field, promotes interactions among junior and established investigators through poster sessions, oral presentations and organized networking opportunities. Ample opportunity will be provided to junior scientists and trainees to present thei findings and travel grants awarded to encourage their participation. There will also be strategic efforts to promote attendance and engagement of underrepresented groups in science.